edu.cmu.sphinx.frontend.endpoint
Class SpeechMarker

java.lang.Object
  edu.cmu.sphinx.util.props.ConfigurableAdapter
      edu.cmu.sphinx.frontend.BaseDataProcessor
          edu.cmu.sphinx.frontend.endpoint.SpeechMarker

All Implemented Interfaces:

DataProcessor, Configurable

public class SpeechMarker
extends BaseDataProcessor

Converts a stream of SpeechClassifiedData objects, marked as speech and non-speech, and mark out the regions that are considered speech. This is done by inserting SPEECH_START and SPEECH_END signals into the stream.

The algorithm for inserting the two signals is as follows.

The algorithm is always in one of two states: 'in-speech' and 'out-of-speech'. If 'out-of-speech', it will read in audio until we hit audio that is speech. If we have read more than 'startSpeech' amount of continuous speech, we consider that speech has started, and insert a SPEECH_START at 'speechLeader' time before speech first started. The state of the algorithm changes to 'in-speech'.

Now consider the case when the algorithm is in 'in-speech' state. If it read an audio that is speech, it is scheduled for output. If the audio is non-speech, we read ahead until we have 'endSilence' amount of continuous non-speech. At the point we consider that speech has ended. A SPEECH_END signal is inserted at 'speechTrailer' time after the first non-speech audio. The algorithm returns to 'out-of-speech' state. If any speech audio is encountered in-between, the accounting starts all over again. While speech audio is processed delay is lowered to some minimal amount. This helps to segment both slow speech with visible delays and fast speech when delays are minimal.

Field Summary

static java.lang.String	PROP_END_SILENCE A property for the amount of time in silence (in milliseconds) to be considered as utterance end.
static java.lang.String	PROP_END_SILENCE_DECAY A property to decrease end silence while we are reading speech.
static java.lang.String	PROP_SPEECH_LEADER A property for the amount of time (in milliseconds) before speech start to be included as speech data.
static java.lang.String	PROP_SPEECH_LEADER_FRAMES A property for number of frames to keep in buffer.
static java.lang.String	PROP_SPEECH_TRAILER A property for the amount of time (in milliseconds) after speech ends to be included as speech data.
static java.lang.String	PROP_START_SPEECH A property for the minimum amount of time in speech (in milliseconds) to be considered as utterance start.

Constructor Summary

SpeechMarker()

SpeechMarker(int startSpeechTime, int endSilenceTime, int speechLeader, int speechLeaderFrames, int speechTrailer)

Method Summary

int	getAudioTime(SpeechClassifiedData audio) Returns the amount of audio data in milliseconds in the given SpeechClassifiedData object.
Data	getData() Returns the next Data object.
void	initialize() Initializes this SpeechMarker
boolean	inSpeech()
void	newProperties(PropertySheet ps) This method is called when this configurable component needs to be reconfigured.

Methods inherited from class edu.cmu.sphinx.frontend.BaseDataProcessor

getPredecessor, getTimer, setPredecessor

Methods inherited from class edu.cmu.sphinx.util.props.ConfigurableAdapter

getName, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

PROP_START_SPEECH

@S4Integer(defaultValue=200)
public static final java.lang.String PROP_START_SPEECH

A property for the minimum amount of time in speech (in milliseconds) to be considered as utterance start.

See Also:

Constant Field Values

PROP_END_SILENCE

@S4Integer(defaultValue=500)
public static final java.lang.String PROP_END_SILENCE

A property for the amount of time in silence (in milliseconds) to be considered as utterance end.

See Also:

Constant Field Values

PROP_SPEECH_LEADER

@S4Integer(defaultValue=50)
public static final java.lang.String PROP_SPEECH_LEADER

A property for the amount of time (in milliseconds) before speech start to be included as speech data.

See Also:

Constant Field Values

PROP_SPEECH_LEADER_FRAMES

@S4Integer(defaultValue=30)
public static final java.lang.String PROP_SPEECH_LEADER_FRAMES

A property for number of frames to keep in buffer. Should be enough to let insert the SpeechStartSignal.

See Also:

Constant Field Values

PROP_SPEECH_TRAILER

@S4Integer(defaultValue=50)
public static final java.lang.String PROP_SPEECH_TRAILER

A property for the amount of time (in milliseconds) after speech ends to be included as speech data.

See Also:

Constant Field Values

PROP_END_SILENCE_DECAY

@S4Double(defaultValue=15.0)
public static final java.lang.String PROP_END_SILENCE_DECAY

A property to decrease end silence while we are reading speech. This allows marker to adapt to the fast speech with small pauses. This is relative decrease to speechTrailer per second of speech, so that utterance shouldn't be longer than this amount of seconds.

See Also:

Constant Field Values

Constructor Detail

SpeechMarker

public SpeechMarker(int startSpeechTime,
                    int endSilenceTime,
                    int speechLeader,
                    int speechLeaderFrames,
                    int speechTrailer)

SpeechMarker

public SpeechMarker()

Method Detail

newProperties

public void newProperties(PropertySheet ps)
                   throws PropertyException

Description copied from interface: Configurable

This method is called when this configurable component needs to be reconfigured.

Specified by:

newProperties in interface Configurable

Overrides:

newProperties in class ConfigurableAdapter

Parameters:

ps - a property sheet holding the new data

Throws:

PropertyException - if there is a problem with the properties.

initialize

public void initialize()

Initializes this SpeechMarker

Specified by:

initialize in interface DataProcessor

Overrides:

initialize in class BaseDataProcessor

getData

public Data getData()
             throws DataProcessingException

Returns the next Data object.

Specified by:

getData in interface DataProcessor

Specified by:

getData in class BaseDataProcessor

Returns:

the next Data object, or null if none available

Throws:

DataProcessingException - if a data processing error occurs

getAudioTime

public int getAudioTime(SpeechClassifiedData audio)

Returns the amount of audio data in milliseconds in the given SpeechClassifiedData object.

Parameters:

audio - the SpeechClassifiedData object

Returns:

the amount of audio data in milliseconds

inSpeech

public boolean inSpeech()